Two scale simulation of surface stress in solids and its effects

摘要

Surface stress in solids can have profound effects in semi-infinite and nanoscale materials. The current work pertains to the simulation of surface stress, using the concept proposed by Shuttleworth [Proceedings of Physical Society 63 (1949) 444-457]. A two-scale approach is used for the simulation of surface stress. Density functional theory is used to compute the lattice parameter of a free-standing layer (or two layers in the case of (1 10) surface) of atoms, which is further used as an input into a finite element model. Aluminium is used as a model material for the computation of surface tension of (10 0), (1 1 1) and (1 10) planes and the results of the simulations are validated by comparison with results from literature. The utility of the model developed is highlighted by demonstrating the effect of surface tension on the: (i) stress variation in a thin slab & (ii) lattice parameter of nanoscale free-standing crystals. (C) 2016 Elsevier B.V. All rights reserved.